1. Field of the Invention
The present invention relates to a tandem printers system including a first printer capable of printing primary page images on a continuous sheet and a second printer capable of printing secondary page images, related to the corresponding printed primary page images, on page sections regulated by the printed primary page images on the continuous sheet.
2. Description of the Prior Art
In general, a tandem printers system is utilized to realize a high-speed duplex printing as well as a high-speed spot color printing on a continuous sheet such as continuous forms. In the case of the duplex printing, for example, a first printer such as a high-speed page printer is designed to print front side page images on the front surface of continuous forms. After the front side page images have been printed, the continuous forms are transferred to a second printer such as another high-speed page printer. The second printer is designed to print reverse side page images on the reverse surface of the continuous forms.
When a jam takes place at the second printer in the tandem printers system, the first and second printers stop the printing operation. The first printer then returns to the printing operation. The first recovery page of the first printer is determined based on the reverse side page image printed last at the second printer. For example, if a jam happens at the second printer during the printing operation of the reverse side page image on the fifteenth (15th) page sections on the reverse surface of the continuous forms, the first printer recovers the printing operation for the front side page image corresponding to the fifteenth (15th) page sections on the front surface of the continuous forms.
The tandem printers system is usually designed to reserve the continuous forms, corresponding to a series of a large number of forms or page sections, between the first and second printers. The reserved continuous forms may contain a series of twenty (20) forms or so. For example, when the second printer is printing the reverse side page image of the fifteenth (15th) page section in the aforementioned manner, the first printer may be printing the front side page image of the thirty-fifth (35th) page section. If a jam takes place at the second printer in this situation, the first printer is expected to return to the printing operation for the front side page image of the fifteenth (15th) page section. The reserved continuous forms with the printed front side page images between the first and second printers is simply torn off and destroyed.
It is accordingly an object of the present invention to provide a tandem printers system capable of minimizing the loss of a continuous sheet reserved between first and second printers even when a jam happens at the second printer.
According to a first aspect of the present invention, there is provided a tandem printers system comprising: a first printer printing primary page images on a continuous sheet; a second printer printing secondary page images, related to the primary page images, on page sections regulated by the primary page images on the continuous sheet; and a controller determining a first recovery page for the second printer based on a printed page at the first printer when at least one of the page sections is removed from the continuous sheet before establishment of the secondary page images.
The tandem printers system serves to print primary and secondary page images on the front and back surfaces of the continuous sheet, respectively. Duplex printing is thus accomplished on the continuous sheet. Otherwise, the tandem printers system serves to sequentially print the primary and secondary page images on the common front surface of the continuous sheet. So-called spot color printing can thus be realized on the continuous sheet. When a jam happens at the second printer, at least one of the page sections is removed from the continuous sheet before establishment of the secondary page images. The first recovery page for the second printer after the removal of the page section can be determined based on the printed page at the first printer. The printed page of the first printer is expected to exist on the continuous sheet reserved between the first and second printers, for example. Accordingly, it is not necessary to remove the entire continuous sheet remaining between the first and second printers when the printing operation should be recovered. It is possible to minimize the loss of the continuous sheet reserved between first and second printers even when a jam happens at the second printer. The controller may be incorporated within any of the first and second printers, or within a separate controller apparatus connected to the first and second printers.
The controller is preferably designed to determine the missing page for the second printer based on the first recovery page and the last printed page at the second printer. Determination of the missing page in this manner leads to a reliable establishment of the primary and secondary page images on the continuous sheet based on the determined missing page.
Upon the establishment of the secondary page image, printing data of the secondary page image corresponding to the missing page may be stored in a storage medium when the jam happens at the second printer. The second printer may simply be designed to read out the printing data of the secondary page image from the storage medium when printing the secondary page image. In addition, printing data of the primary page image related to the missing page for the second printer may also be stored in the storage medium. The first printer may simply be designed to read out the printing data of the primary page image from the storage medium when printing the primary page image. The storage medium may be a magnetic recording disk such as one incorporated within a hard disk drive (HDD) or a diskette drive, a volatile or non-volatile memory, or the like.
In the tandem printers system, the first recovery page for the first printer may be determined based on the last printed page for the first printer. Specifically, the first recovery page of the first printer can be determined irrespective of the last printed page of the second printer. The primary page images can be printed on the continuous sheet in a predetermined sequence or schedule, without any change or skip, in the first printer. The control of the first printer can be facilitated.
Here, the first printer may continue printing the primary page image for a predetermined number of page when a jam happens at the second printer. The continuation of the printing in this manner leads to reserve of the enough continuous sheet between the first and second printers even when the continuous sheet is pulled into the second printer prior to the recovery of the printing operation.
According to a second aspect of the present invention, there is provided a tandem printers system comprising: a first printer printing primary page images on a continuous sheet; a second printer printing secondary page images, related to the primary page images, on page sections regulated by the primary page images on the continuous sheet; and a controller determining a first recovery page for the first printer based on a last printed page at the first printer when a jam happens at the second printer.
The tandem printers system serves to print primary and secondary page images on the front and back surfaces of the continuous sheet, respectively. Duplex printing is thus accomplished on the continuous sheet. Otherwise, the tandem printers system serves to sequentially print the primary and secondary page images on the common front surface of the continuous sheet. So-called spot color printing can thus be realized on the continuous sheet. When a jam happens at the second printer, at least one of the page sections is removed from the continuous sheet before establishment of the secondary page images. The first recovery page for the first printer after the removal of the page section can be determined based on the last printed page at the first printer. The primary page images can be printed on the continuous sheet in a predetermined sequence or schedule, without any change or skip, in the first printer. The control of the first printer can be facilitated.
It should be noted that the first and second printers may take any form such as page printers, dot matrix printers, ink jet printers, copying machines, facsimile machines, or the like.